ross100

Took my atomic SR85 out on the large pond and thought I was going to loose it. I followed you tube video perfectly and put rudder on, grease it etc. Went not bad for a minute or so, then chugged and stopped and did small circles when throttled. Never looked like getting up to speed is capable off, looked a bit one sided to with two 2S lipos. I want to cry now, that was my first run with out out the box. Sniffff Snifffff!!

I will maybe concentrate on The valvryn first and translate this knowledge onto atomic later. I’m learning fast that rtr out of the box, really doesn’t mean ready to run, needs tweaks and checks like you told me. No idea why but the atomic eventually go in a very slow straight line and limp back to me. At least I didn’t lose it, still super keen to learn and master the basics. Will have to take out the mad flow next time to boost my confidence. Kindest Regards.

Ross

ps will put my atomic in box now and concentrate on valvryn. At least my mad flow still works fine, and this seems to be as fast as my atomic and valvryn speeds so far. Not to bother, am sure when get the Valvryn set up with your expert guidance, will deliver in performance eventually. Thanks

ross100

Pps do all boats take in a certain volume of water into hull or is that because they are not set up properly. I’m super keen to learn.

ross100

Just opened the valvryn box, it’s got a dent and touch up on right hand side of hull, so has to be sent back, not spoken to this model shop yet, just emailed.

It has light scratches on right hand use of hull to, so not new and I paid £320 for a new one to them. Could we switch to helping me with the atomic, while this is hopefully getting sorted out

Hydro Junkie

I'm watching a video on the Atomic right now and see some things that I'd change:
1) I see the same issue with this boat as I did with the other, the drive shaft is too tight.
2) Did the 2S battery come with it or did you have to buy them? The video I saw showed a 3S 11.2volt pack. A 3S will be faster than a 2S
3) That plastic prop has got to go. Plastic props tend to flex under load and will break. I know of someone that can sell you a sharpened, polished and balanced replacement that will outperform that plastic one though, unfortunately, it won't be real cheap and, if you get your finger in the way, it could take it off
I was doing a bit of research and found this is, more or less, a toy grade boat. I'm assuming the same with the Valvryn. These are not really set up or made for going real fast. I did see a review video on this boat, which showed an issue with the test boat as well, the link being below. let me know if any of this is what you were seeing.

ross100

Hi there, thank you for the reply. I paid think it was £230. Thank you for watching the videos. The propeller on mine Is metal and I had to buy two 2S lipos separate. I actually have a single 4S on order which think will give me more power with weight to power ratio. I watched a 12/13 minute vid on attaching the rudder on you tube.

To be honest, feel really disheartened about getting that defected valvryn today after paying £320. I really hope they don’t take the approach tomorrow that I did it as only opened the box at 7.30pm after it arrived at 4pm. Actually feel quite sick.

ross100

The atomic came with all the right hex drivers and that, so will definitely be able to get the flex cable out.

ross100

Ps do you have a contact that stays in Moray that can could help me

ross100

Ps mine is the atomic SR85 model. Cheers

Hydro Junkie

Would I be correct in that being Moray Firth, Scotland?
I would contact Mfr02, here in the forum. He would be a better source of help than I since he lives in Blackpool Lancs. I'm almost half a world away, being on the US northwest coast, just north of Seattle

ross100

Can I send you a pic of my atomic inside as not sure what to loosen between motor and shaft to get flex line out for lubrications. How do I attach a picture if that’s ok? Cheers

Ross

ross100

Can I send you a pic of my atomic inside as not sure what to between motor and shaft to get flex line out for lubrications. How do I attach a picture if that’s ok? Cheers

Ross

Hydro Junkie

Actually, it's very easy to get out the shaft. Let me go through it, step by step:
1) find the motor
2) on the motor shaft, there is a piece that's bigger just before the shaft goes through the bottom of the boat
3) rotate the motor until you find the screws in that larger piece on the motor shaft
4) loosen the screw closest to the rear of the boat
5) pull out the drive shaft by the prop
Now that you have it out, give it a good coating of a water proof grease, preferably lithium based. Be sure not to get any on the area that goes into the bigger part on the motor shaft. In fact, you may want to leave the last couple of cm bare of grease
Once you have that completed, you can re-install the shaft. One other thing you COULD do, while the shaft is out, is to drill a small hole(maybe 2mm or slightly larger, if there isn't one already) through the side of the strut(the part just ahead of the prop and drive dog when the shaft is installed) so you can inject grease into it between runs
When you have the shaft back into the boat, you will need to tighten the screw that holds the shaft in. Before you do so, take it totally out, coat it with thread lock(orange or blue only, not red as red requires heat to get the screw out later)
When you're tightening the screw, make sure to leave a small gap between the strut and drive dog. This needs to be at least 2-3mm, so that the shaft won't bind when running. If it binds, remove the screw again, recoat with thread lock and reinstall, leaving a larger gap each time until it doesn't bind. You do need to be careful as if you go too far, the shaft won't have enough length left inside the coupler to hold it and you could lose the prop and shaft to the bottom of the pond. For example, on my sport 20 hydroplane, it has a .187 inch(4.75mm) shaft, similar to what your boat has except larger. To allow for it to "shrink" under load, I leave a 5mm space between the drive dog and the strut. This prevents the shaft from binding. I'll try to get a picture of it later today so you can look at it

ross100

Hey, hope that you are qwell. Can you give me an email address and will send a pic of inside the atomic and you can tell me what to loosen. Cheers

Ross 🙂

Hydro Junkie

As I said in a previous post;
1) look at the motor. coming out of the motor is a shaft that points down and rearward
2) between the motor and the back of the inner compartment is a metal fitting with two socket head screws
3) remove the lower screw
4) pull the shaft out by the prop
5) apply grease to most of the shaft, leave the top end(opposite end from the prop free of grease so it can't slip when reinstalled
6) slide the shaft back in to the boat, leaving a gap between the outdrive(the black plastic thing that turns back and forth at the back of the boat) and the drive dog) the silver thing that's in front of the prop
7) apply thread lock(orange or blue colored) to the threads of the screw and reinstall it, make sure it's snug but not smashing the shaft.
If you watch the following video, pause it at 1:02, it will clearly show the metal fitting and socket head screws
Something else to check is the clear tubing that goes to the motor. Make sure it's not damaged as they supply water to the motor to keep it cool. If they are damaged, it will quickly flood the boat with water, ruining the receiver and speed controller

ross100

Hey bud, cheers for all your time and help. The valvryn has been posted back as it had the defect. Will defo follow all your advice when it arrives. Is was my green atomic SR85 I was asking about, you couldn’t tell us how to remove the flex tube from that.

Really sorry for confusing you and the mix up in my last post.

Ross

Hydro Junkie

Actually, the removal and installation is very similar. Just look in the same location as shown in the video above, between the motor and shaft tube. You will see a cone shaped part screwed onto a hex shaped part. These two parts, plus one inside, are called a collet assembly. You will need a pair of appropriately sized wrenches or, if you don't have them, adjustable wrenches. You just hold the hex shaped part with one wrench and turn the cone shaped part toward the boat's left side to loosen, then the shaft should pull right out. You don't have to totally disassemble the collet or use thread lock on it. Otherwise, the process for both boats is the same. Be sure to leave a gap between the prop drive dog and the rear of the part the shaft comes through. One thing that would help is to know how thick the drive shaft is. If you have some way to measure it, it would be a great help

ross100

Thanks bud, think I’ve got that! Ordering two adjustable wrenches on amazon now. Not sure what you mean about leaving the gap, what’s the dog thing you mention? Warmest Regards.

Ross

ross100

Ps yes sir, will get the thickness of the drive shaft to you. Thanks a mill, you’re teaching me a lot here, much appreciated.

Ross

ross100

Hey man, got the flex tube out of the atomic with your amazing advice, you are a superb teacher! I used two 10mm wrenches and followed your advice. Well done. Can you tell me please how far along I grease the cable before putting it back on and where to leave the gap. Warmest Regards.

Ross

ross100

Since the boat drive uses a twisted cable to drive the prop, make sure there's space between the prop drive dog and the outdrive. If there isn't any or very little space, you will have the same issues as the other boat
2) On the motor output shaft, there is a coupler that connects the cable to the shaft. You need to remove the retaining screw that holds the cable. Pull the cable out, by the prop, and make sure it has some grease on it. If it looks dry, don't try to run it until you can grease the cable. Be sure to NOT get grease on the end where it goes into the coupler or it could spin or, worse yet, come out on the water. Make sure, when you put the retaining screw back in, that you use blue or orange thread lock on the threads

Hey bud, I have just read all your posts again to me and it’s making a lot more sense now. Sorry if I am asking same questions again, but in terms of my atomic SR85, green one. I watched the red atomic vid you sent from Aussieland and that looks a much smaller one. I have pasted some of your post above to ask some questions please. I have flex cable out Of atomic SR85 and will marine grease soon.

i don’t understand what means when you say to make sure there's space between the prop drive dog and the outdrive.

You also said chief, cable. Be sure to NOT get grease on the end where it goes into the coupler or it could spin or, worse yet, come out on the water. Make sure, when you put the retaining screw back in, that you use blue or orange thread lock on the threads.

Think understand that can’t get grease on metal rod Of motor or Flex cable that goes into collet assembly, is that right bud? I’m totally confused where to put the blue thread lock, I’ve ordered the blue one on amazon after you advised me in terms to stop the binding.

you also said leave space between the outdrive (whats the outdrive again)? Is that the silver tube bit on the atomic that is behind the gold thing with the grub screw behind the propeller. You said it turns back and forth at the end of the boats drive dog. Is the drive dog on my atomic SE85 the bit with the grub screw behind the motor? You said think the drive dog is the silver bit in front of the propeller.

Sorry so many questions, but should the propeller be be bolted tight to that bit with the grub screw behind it or is that where I leave the 2 to 3mm gap as know you said flex cable shrinks when under load when boat is running. Hope you’re well and thanks for everything.

Ross

Hydro Junkie

Okay, I'll try to make this as easy as possible:
1) Since you now have the shaft out of the boat, you can see it's a cable. They used a cable to make it so the drive shaft doesn't have to be straight.
2) Unfortunately, since they used a cable, it requires greasing to it doesn't drag on the inside of the tube. IF it drags on the inside of the tube, it will drain your batteries faster and can cause issues with the motor and speed controller, starting with getting hot.
3) As far as where NOT to apply grease, leave the end that doesn't have the prop bare for the last half inch or last 1.5cm. This is where the collet clamps down on the cable and holds it in the boat. IF grease gets there, it will affect how well the collet holds the shaft
4) At the prop end of the drive shaft, you need to make sure the nut holding the prop against the silver drive dog is snug. If you go too tight, it will damage the prop. In fact, I would recommend a metal prop instead of that plastic one as plastic props flex under load, costing you speed and, unlike a metal prop, the plastic ones can and will break
5) When you reinstall the shaft, you need to leave room between the drive dog and the black part that's bolted to the back of the boat. That part is called a strut It's job is to make adjusting the props's depth and angle, things you don't need to worry about now. The reason you need to leave a gap between the silver drive dog and the black strut is that the drive shaft will shorten under load. When that happens, it will drag on the strut, again costing speed and using up your battery faster. IF the cable is long enough, you need to leave a space between the drive dog and strut, preferably a wide as the cable is thick. That is the general rule we use when setting up our racing boats. What can help you to know if you have enough cable to leave that big of space is to put the shaft back in but don't put it into the collet just yet. INSTEAD, stop when the cable reaches the collet and measure how much cable there is between the strut and the drive dog. This is important as it will tell us how much cable we will have inside the collet when the cable is tightened. This is also why I asked how thick the cable is.

ross100

Hey bud, I must stop and just thank you again profusely for all the time and effort you have invested in me to solve my problems with the atomic SR85. You have just taught me so much and enthused next about continuing with rc speed boats and to learn more. I’m a teacher myself (not physics though!) and you have just conveyed everything to me with crystal clarity. I would really like to send you something from Scotland to say thank you and keep you as a bud/ rc boat mentor in the future.
Totally understand though if you have had enough of me though!

I have followed your most recent list and think I’ve done it on my atomic! Hooorah!! Well, will better refrain from being too cocky and wait until it’s run on the stand and out on the large boating pond where I live. The boat does have a metal propeller and I’ve ordered another metal one to replace the plastic one in my other boat.

Chief, where do I put that blue thread lock again which still waiting from Amazon for, I didn’t understand that bit? I measured the thickness of the flex cable which is 4mm and left that distance between the drive dog and the silver vertical attachment bit on the atomic (not black like on valvryn). Think you said this vertical attachment bit on rear of boat relates to propeller angle/depth, But I don’t need to worry about that. Left motor end ungreased as you said for 1.5cm length. I had about 1.8cm of the flex cable free I think when just reached the collet like you asked me to do, so 4mm space from between drive dog and silver vertical bit not a problem. Interesting that this space has to equal the cable thickness, didn’t know this rule and sobering else I’ve learnt from you.

I got my money back for the Valvryn just to keep you in the loop. I’ve decided not to buy another One, despite love how the valvryn looks. I’ve read mixed things about it and watched experienced people on you tube saying it only does about 25mph and sounds rough and not 30mph plus like it says on the box with 4S. I’m going to run the atomic and with your help if you agree. Then I will buy another boat with my valvryn money, so feel free to recommend a rtr self righting boats to me that run on 3S 5000mAh 11.1V lipos as now have two unused which bought with valvryn.

Kindest Regards bud and look forward to hearing from you.

Ross 👍🏻😎👍🏻

ross100

Could you help me source a metal propeller to replace my plastic one please on my joysway mad flow boat. The nylon one has p1.4D35mm on it, whatever that means. Think you said metal and two blades will go faster rather than three blades. Thanks a mill chief, was looking on amazon there. Warmest Regards.

Ross

Hydro Junkie

Okay, let's take this one item at a time:

• Thread lock goes anywhere you have a screw that is on a moving part. Your Atomic won't need it unless you want to make sure the screws holding the rudder assembly or motor to mounts won't back out. Thread lock is not needed any place you have locknuts as the nuts serve the same function. You would have needed it on the shaft coupling on the Valvryn.
• So you understood about the spacing between the prop and strut, that's great to read. You probably noticed that the spacing is now considerably more than when you got the boat, something the people building them didn't understand or even know about. I'm just glad to read that you had the 1.4cm to go into the collet, shouldn't be an issue. I know, with a boat I built, it has a 47.4mm shaft so, when I cut it to length, actually had to do just the opposite. I had to put it all the way into the collet, measure the remaining space between the drive dog and strut, and cut it to length after doing the math. This is the advantage of cutting your own shafts, I don't have to measure it again, just stuff it in all the way and tighten the collet

Now, let's talk props. I'm far from an expert on them but what you gave, P1.4 D35mm means it's a standard size prop. The P 1.4 is talking about the blade pitch. In this case, the pitch is 1.4 times the diameter, given as D35mm. When you do the math, it works out to 1.4X35=49mm. 49mm is how far forward the boat should move forward for each full turn of the prop, IN THEORY. Like anything else, you won't get quite that much do to slippage or lost thrust due to various reasons. As for a source for props, I would refer you to a man here in the US, Mark Sholund. I recommend him for two reasons:
1) He does good work. Props he sells are balanced, sharpened and polished, unlike the props you buy online or from hobby shops where they are rough castings or crudely finished.
2) I've dealt with him so I know he's honest and fair. If he has the prop you need, ready to go, it will be shipped within a few days. If not, he will get one ready and ship within a few days of getting it done.
His website is:
www.props4u.net
His email address is
[email protected]
Next, the number of blades:
2 Blades

• easier to balance since they are located directly across the drive shaft from each other
• has a higher top speed due to less drag in the water

3 Blades:

• harder to balance as you're dealing with three points, 120 degrees apart
• accelerates faster due to 50% more push, IN THEORY
• helps the boat corner faster to one side when used in a surface drive set up

ross100

That’s ace chief, will get onto the prop guy straight away. Thanks so much for that Info. You have Taught me a lot about propellers andI will use the thrust/load principles when teaching my second year science classes in the future! Mentioning you of course you’re good self as the donor of the specialised knowledge.

No worries about the thread lock, will have the blue stuff for future reference when it arrives. Yes, I’ve learnt quickly rtr just means assembles, not tweeted for maximum performance. Will keep you posted bud, have a great day and talk soon.

Ross 👍🏻😎👍🏻

Ps you dodged my question about sending you something from Scotland to say thank you. Hope that you’re not being too modest [img]blob:https://www.rcuniverse.com/91aa4cf0-3293-46ac-ae36-0665db455f4e[/img]